An indirect pulp cap for primary teeth is performed when?

An indirect pulp cap for primary teeth is indicated in situations where the walls of the cavity are extended to sound tooth structure. This approach is taken in cases where there is a risk of pulp exposure due to residual carious dentin but where the pulp is still healthy. The technique involves leaving a layer of carious dentin over the pulp to maintain vitality and allow for the formation of secondary dentin, which can help protect the pulp.

In contrast, performing an indirect pulp cap on teeth with irreversible pulpitis would not be appropriate, as the condition indicates that the pulp is already damaged and not capable of healing. Removing all caries implies that the risk of pulp exposure is mitigated, which would not warrant an indirect pulp cap, as it's typically used when some carious dentin is intentionally left behind. Lastly, always conducting the procedure in a two-step manner is not a requirement; indirect pulp capping can sometimes be achieved in a single visit, depending on clinical judgment and the specific case.